Glycinin is a major soybean seed storage protein used extensively in soy food products. However, these proteins have functional properties that do not make them ideally suited in all product applications.
It has been found that the functional properties (emulsification, gelation, solubility, etc.) of a protein are directly related to amino acid composition, sequence, and structure. Therefore, the properties can be altered through protein engineering.
Currently, improvement in soy protein functionality has been achieved through protein engineering of the core amino acid sequence. However, these alterations are limited due to the necessity of maintaining the wild-type three-dimensional structure so that the protein can assemble correctly.
The present invention provides methods and compositions for changing the properties of glycinin without having to alter the core structure responsible for correct assembly. This approach provides greater flexibility, allowing more radical changes than might be tolerated by alterations to the native protein structure.